Lupus Anticoagulant Evaluation : 1003009

The aliquots must remain frozen. Freeze thaw cycle will adversely affect specimen integrity. CRITICAL FROZEN: Separate specimens must be submitted when multiple tests are ordered.

Test Code
LAEVAL or 1003009

Alias/See Also
Staclot LA; Lupus Anticoagulant; DRVVT; LA

CPT Codes
85610, 85730, 85613

Panel includes: PT, APTT, and Dilute Russell Viper Venom Time and possible reflex tests of Thrombin Time; DRVVT 1:1 screen and/or confirmation; Heparin, Anti-Xa, Unfractionated; or Hexagonal Phase Phospholipid Neutralization.

If APTT is prolonged, Thrombin Time will be performed at an additional charge (CPT code(s): 85670).
If the Thrombin Time is prolonged, then Heparin, Anti-Xa, Unfractionated will be performed at an additional charge (CPT code(s): 85520).
If the DRVVT screen is prolonged, DRVTT Confirm will be performed at an additional charge (CPT code(s): 85597).
If the screen/confirm ratio is prolonged then DRVTT 1:1 Mix will be performed at an additional charge (CPT code(s): 85613).
If the DRVTT Screen is not prolonged and/or the screen/confirm ratio is not prolonged, then testing reflexes to Hexagonal Phase Phospholipid Assay will be performed at an additional charge (CPT code(s): 85598).

Blue top tube, 3.2% sodium citrate.
• Obtain venous blood by clean venipuncture. Avoid slow-flowing draws and/or traumatic venipunctures as either of these may result in an activated or clotted specimen. Do not use needles smaller than 23 gauge. Do not leave the tourniquet on for an extended length of time before drawing the sample.
• A pilot tube (non-additive or light blue tube) before drawing coagulation specimens in light blue vacuum tubes is only necessary when using a butterfly blood collection set as this will cause reduced draw volume in the first tube. Discard the pilot tube.
• Fill light blue tubes as far as vacuum will allow and mix by gentle inversion. Exact ratio of nine parts blood to one part anticoagulant must be maintained. Inadequate filling of the sample tube will alter this ratio and may lead to inaccurate results. Patients who have hematocrit values above 55 percent should have the anticoagulant adjusted to maintain the 9:1 ratio. Use the following formula to determine the amount of anticoagulant to use: [(100 – Hct) / (595 – Hct) ]* total volume = amount of anticoagulant required.
• After collecting the blood, examine the tube to ensure that it is filled to within 90% of the fill line.
• Note: Specimens containing heparin should not be used for coagulation studies. If possible, stop heparin therapy before the draw to avoid contamination. Heparin interferes with most clotting assays. If heparinized line must be used to obtain the sample, flush line with 5mL saline and discard the first 5 mL of blood drawn into a syringe, or 6 “dead space” volumes of the line.

Transport Container
Centrifuge the blue top tube(s) at a rate of speed to yield platelet-poor plasma (<10,000/uL). Immediately remove the top three-fourths of the platelet-poor plasma from the specimen using a plastic transfer pipet (use of glass transfer pipets may result in activation and/or clotting of the plasma) and transfer into a new plastic tube. Centrifuge a second time and transfer the top three-fourths of the plasma from the second spin into 2 standard transport tubes (min. 1 mL each) and freeze the aliquots.

Transport Temperature

Specimen Stability
After separation from cells: Ambient: Unacceptable; Refrigerated: Unacceptable; Frozen: 14 days

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
.Hemolysis; marked icterus; marked lipemia; received thawed; received refrigerated; received room temperature

Clotting; (reflex testing includes Chromogenic)

Setup Schedule
Monday & Wednesday & Friday

Report Available
1-4 days

Reference Range
Lupus Anticoagulant: Not detected
Refer to laboratory report for other analytes.

Clinical Significance
Lupus Anticoagulants (LAs) are associated with numerous clinical states such as systemic lupus erythematosus, recurrent spontaneous abortions, thrombosis, and infections. Their presence may be persistent or transitory. The diagnosis of LA is often difficult because of variable reagent sensitivity and the intrinsic heterogeneity of LA.
This test is a reflexive test that is based on the following criteria:
Performing two or more phospholipid dependent clotting tests and demonstrating prolongation of at least one.
Evidence of inhibitor activity in patient plasma when mixed with normal plasma.
Evidence of phospholipid dependence of the inhibitor on a confirmatory test by shortening the clotting time with the addition of more phospholipid.
Absence of a specific inhibitor against a coagulation factor.

Performing Laboratory
med fusion

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.